getting to grips with the cost index(11)

曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

The three tables shown in Appendix 4 for respectively the A340-311, -312, -211, and -212, for the A340-313 and A340-313E, indicate the preselected climb IAS to be entered and the resulting Climb MACH, corresponding to the FMS output displayed in small font on MCDU PERF CLIMB page.
- 
The preselected climb speed mode allows the introduction of a IAS only, the climb Mach then being computed against this IAS. With these tables it is therefore possible to choose the preselected IAS and ECON CLIMB MACH before these are to be part of FMGEC Load 7 when available later in 1997.

- 
The Tables of Appendix 4 are limited by the Max Altitude in ISA conditions. However, the speeds provided are available for any temperature. In ISA deviation conditions, Cruise Altitude has to be limited by the FMGS predicted Max Altitude.

- In order to perform strict minimum distance to climb, green dot should be
selected or an altitude constraint should be inserted on a waypoint in the FMS.

 

6. OPTIMUM ALTITUDE FOLLOW-UP
6.1 Trade-off between manoeuvrability and economy
In general, numerous parameters such as weather conditions or ATC requirements could influence any decision made by the crew, with regard to three fundamental priorities :
-manoeuvrability
-comfort
-money saving economy
This pertains to the choice of the cruise FL which can be made according to the following three climb profiles between optimum and maximum altitude
Figure 14.

-
best order for improved manoeuvrability margins : 3, 2, 1

-
best order for money saving economy : 2, 3, 1

 

Contrary to some opinions, solution . is neither worthwhile for comfort nor for economy. Other considerations could lead to a higher FL being chosen for meteorological or operational reasons but, in any case, flying above optimum altitude commands particular attention.
On all Airbus FMS-equipped aircraft, OPT FL (taking into consideration aircraft gross weight, cost index (i.e speed), wind...) and MAX FL are displayed in the MCDU progress page. The recommended MAX FL in the FMGC ensures a 0.3 g buffet margin, a minimum rate of climb of 300 ft/min at MAX CLIMB thrust as well as level flight at MAX CRZ thrust. The 1.3 g maximum altitude is always above maximum propulsion altitude.
The pilot has to manage step climbs according to traffic, ATC requirements and values of OPT and MAX FL which differ according to the following values for each Airbus type :
Table 8 bis. OPTIMUM and MAXIMUM altitude
Types  Approximate difference betweenOPT and Max FL 
A300/A310  4000 ft 
A319  4000 ft 
A320  3000 ft 
A321  3500 ft 
A330 GE  3500 ft 
A330 PW  3500 ft 
A330 RR  3000 ft 
A340  2500 ft 

Furthermore, a 4000ft step climb between OPT -2000ft and OPT+2000ft is to be performed when possible, when to minimize fuel consumption by choosing cruise FL segments as close as possible to the OPT FL.
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：getting to grips with the cost index(11)